This important publication addresses intercellular communication in health and disease. It includes recent advances in morphology and chemical organization of gap junctions. It discusses the possible role of intercellular channels in excitable and non-excitable tissues. The book presents modulation of junctional permeability, as well as the possible role of cell communication in embryonic development and growth. The text concludes with a synthetic view of the role of gap junctions and potential implications to cardiology, oncology, and other areas of pathology. This volume is important to professionals in pharmacology, physiology, biochemistry, biomedical science, pathobiology, pathology, molecular genetics, toxicology and human development.